A quantum computer isn’t just a more powerful version of the computers we use today; it’s something else entirely, based on emerging scientific understanding — and more than a bit of uncertainty. Enter the quantum wonderland with TED Fellow Shohini Ghose and learn how this technology holds the potential to transform medicine, create unbreakable encryption and even teleport information.

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    41 Comments

    1. No sorry, the analogy of the flipping coin is wrong to explain quantum computing. The way she put it is simply like the computer is keeping is results because it as all the information in is hands and not the human player. He will manipulate is coin as he wishes because it can. This is cheating. A game of luck , is a guessing game, being smarter doesn't give you more luck… Being smarter allows you to cheat. I am telling you bad analogy and bad example as a game to test quantum computing.
      By the way, Elon musk braindead fans are already flooding YouTube with videos claiming Elon musk as invented quantum computing…. Elon musk scams continue.

    2. What if the human coin flipper also was given the option of keeping their coin flip decision in a state of uncertainty? Who would win then?

    3. The Q-computer prepares the initial state as |Head> and plays first by choosing either to flip the coin or not, but the outcome is not revealed to the opponent – not even to itself! The opponent plays in the second place akin to the Q-computer. Finally, the Q-computer plays, which is also a measurement revealing the outcome … it’s |Head> and hence, the Q-computer wins, not once, but in every round of the game.

      *

      If the opponent plays first choosing the |Tail>, then obviously, the Q-computer loses every round of the game … which is not all mentioned in this video presentation!!!

      *

      |Head> is like the |y; spin-up> state, prepared initially by filtering it out from the Stern-Gerlach (SG) apparatus with magnetic field direction along Y-axis, by blocking the |y; spin-down> component.

      The |y; spin-up> state then passes through two sequential SG apparatuses [1], but without undergoing any measurement. The magnetic field directions in these two SG apparatuses can be arbitrary.

      The output from the 2nd SG apparatus is subjected to a measurement by the Q-computer using the final SG apparatus with magnetic field direction along Y-axis, akin to the initial SG apparatus.

      It’s very clear from the quantum formalism that the two sequential SG apparatuses in between the initial and final SG apparatuses, simply play the roles of identity operators [1], i.e., every time the |y; spin-up> state passes-out of any one of the two sequential SG apparatuses, it’s in the same |y; spin-up> state and hence, the final measurement obviously results in the |y; spin-up> state. Actually, the presence or absence of the in-between two SG apparatuses doesn't matter, because, they don’t perform any measurement.

      Therefore, the play of Q-computer and the play of opponent are just dubious. In fact, in the case discussed in this video, the Q-computer never performed any quantum computation for winning every round of the game. In other words, it's a game played by the Q-computer with itself = A self-goal (OR) the opponent must be an ignorant to loose every round of the game, because, when the Q-computer shows the initial state, then that's the state to be bet for a win.

      Reference

      [1] J.J. Sakurai, Modern Quantum Mechanics, p 33 (Addison Wesley, 1994).

    4. It's called a guide and not an explanation, which seems proper since there was no explanation, just some examples of what it does. Good intro for me.

    5. I still don't understand the coin example. Even the god doesn't know what I choose, how could the quantum computer win nearly every time? Weird.

    6. Need a computer which think, which feels emotions, a computer which produce apps like man . what is man ? Is a machine who produce apps( applications) ,that would be an attainment

    7. the question of course is does the computer get the information regarding whether I chose to flip the coin and or any other information. There is nothing that a quantum computer can add to the game if the information between the players is fair. Im not sure she is telling us the whole story.

    8. Scientists today are acutely aware of the phenomenal capacity of quantum information processing. For this reason they try in a great hurry to construct so-called “quantum computers”.

      Since quantum information processing is a natural capability of the Universe since its very beginning, it is highly likely that the Universe itself is already using it.

      Unfortunately, the fundamental quantum information processing of the Universe itself is banned from consideration here on Earth.

      In the beginning of the 21st century science firmly believes that the basis of all quantum processes in the Universe is chaos.

      Belief in chaos and randomness of quantum processes was initiated by some famous people in the past century, who failed to imagine an explanation for “apparently random” behavior of elementary particles such as electrons.

      As a result of this glaring lack of imagination, the so-called “uncertainty principle” has been adopted as a foundation of all sciences on Earth.

      The uncertainty principle, in its essence, brutally averages-out all traces of the quantum information processing of the Universe and estimates “probabilities” of some primitive set of locally averaged quantum events.

      The most famous critic of the uncertainty principle as a way to describe the fundamental activity of the Universe was Albert Einstein, who insisted that “God does not play dice”. Unfortunately, like all his contemporaries, he failed to imagine and propose a plausible explanation for apparently random behavior of elementary particles such as electrons. In the absence of intelligent critics, the uncertainty principle gained the status of a sanctified dogma that is not even allowed to be questioned.

      However, quantum-domain information processing in the Universe continues and will continue everywhere, no matter how many authorities and laureates choose to deny it…

    9. If people sent you a square or a circle, how could you program it into your game without knowing its value? I smell a cheat. These results would be too important to be just a boring TED talk. She says during the game the computer generates this fluid quantum bit: This is not quite like the initial game proposed with regular computers where the computer actually flipped ( or not) the coin. I think this is crap.

    10. How about nerves and mushroom connection simulation for nerve chip bridging so paralyzed people can walk again, I just got ideas and no time, not even a cool job, maybe in another life, this one should have been gone 18 times ago : )
      Also would be nice to leave this Universe if I could, maybe someday so other Universe will rescue people stuck in this one

    11. Goddamn it. The more I try to understand it, the more I understand I don't understand it. I thought it was just a simple wave collapse and similar to shrodinger's cat thought experiment where mere observation fixes the electron's state. it's far more complicated since the angle of observation also affects the result you get. So now, the cat is not just dead or alive once you open the box, how you open it will determine whether it's alive or dead.

      So we're still playing with probabilities in quantum entanglement. It is never a straight zero or one.

    12. I've watched a lot of introductory videos about quantum computing, and even took courses for it, but no one explained the basics the way she did. It was so amazing to watch this TED talk!

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